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All-solid-state batteries (ASSBs) containing solid electrolytes can offer high energy density and enhanced safety compared to conventional Li-ion batteries. Among solid electrolytes, sulfide-based materials have garnered significant attention owing to their high ionic conductivity and facile processability. In this study, Li argyrodite solid electrolytes containing both BH4− and Br− anions were prepared using a straightforward two-step milling method without heat treatment. The synthesized materials exhibited an impressive ionic conductivity of up to 14.4 mS cm−1 at room temperature, which surpassed previously reported values of borohydride-substituted argyrodite electrolytes. To elucidate the effect of Br− anion replacement in the thiophosphate local structure, Raman and 31P solid-state nuclear magnetic resonance spectroscopic analyses were performed. The results showed that the total proportion of the PS43− units in the argyrodite phase, including both BH4− and Br− anions, determined the Li ionic conductivity of the solid electrolytes. The prepared solid electrolyte samples were stable up to 5 V vs. Li+/Li without any notable side reactions. The rate performance of the ASSBs, including both the Br− and BH4−-substituted solid electrolytes, was superior to that of the cell with the BH4−-substituted solid electrolyte. [ABSTRACT FROM AUTHOR]

In all‐solid‐state batteries, a solid electrolyte with high ionic conductivity is required for fast charging, uniform lithium deposition, and increased cathode capacity. Lithium argyrodite with BH4− substitution has promising potential due to its higher ionic conductivity compared to argyrodites substituted with halides. In this study, Li5.25PS4.25(BH4)1.75, characterized by a high ionic conductivity of 13.8 mS cm−1 at 25 °C, is synthesized via wet ball‐milling employing o‐xylene. The investigation focused on optimizing wet ball‐milling parameters such as ball size, xylene content, drying temperature, as well as the amount of BH4− substitution in argyrodite. An all‐solid‐state battery prepared using Li5.25PS4.25(BH4)1.75 as the electrolyte and LiNbO3 coated NCM811 as the cathode exhibits an initial coulombic efficiency of 90.2% and maintains 93.9% of its initial capacity after 100 cycles at fast charging rate (5C). It is anticipated that the application of this wet mechanochemical synthesis will contribute further to the commercialization of all‐solid‐state batteries using BH4‐substituted argyrodites. [ABSTRACT FROM AUTHOR]

Background: Although the p.C759F (c.2276G>T, p.Cys759Phe) variant in the USH2A gene has been identified in association with retinal degeneration by several authors, its pathogenicity has been questioned once by the publication of two unaffected homozygotes from a single family. Objectives: The objective of the study was to ascertain the role of p.C759F in hereditary retinal disease. Methods: We examined 87 research articles reporting on patients carrying this variant and then used this information as primary data for a series of meta-analytical tests. Results: Independent statistical analyses showed that p.C759F (i) is highly enriched in patients with respect to healthy individuals, (ii) represents a clear-cut recessive allele causing disease when it is in trans with other mutations, (iii) is pathogenic in homozygotes. Conclusions: Our results confirm that p.C759F is a bona fide mutation, leading to retinal blindness according to a recessive pattern of inheritance. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the morphological changes and molecular structure changes on the surface of single-walled carbon nanotube (SWCNT) films during oxygen plasma (O2) etching of SWCNT surfaces formed by the spray method and analyzed their potential use as electrochemical electrodes. For this purpose, a SWCNT film was formed on the surface of a glass substrate using a self-made spray device using SWCNT powder prepared with DCB as a solvent, and SEM, AFM, and XPS analyses were performed as the SWCNT film was O2 plasma etched. SEM images and AFM measurements showed that the SWCNT film started etching after about 30 s under 50 W of O2 plasma irradiation and was completely etched after about 300 s. XPS analysis showed that as the O2 plasma etching of the SWCNT film progressed, the sp2 bonds representing the basic components of graphite decreased, the sp3 bonds representing defects increased, and the C–O, C=O, and COO peaks increased simultaneously. This result indicates that the SWCNT film was etched by the O2 plasma along with the oxygen species. In addition, electrochemical methods were used to verify the damage potential of the remaining SWCNTs after O2 plasma etching, including cyclic voltammetry, Randles plots, and EIS measurements. This resulted in a reversible response based on perfect diffusion control in the cyclic voltammetry, and an ideal linear curve in the Randles plot of the peak current versus square root scan rate curve. EIS measurements also confirmed that the charge transfer resistance of the remaining SWCNTs after O2 plasma etching is almost the same as before etching. These results indicate that the remaining SWCNTs after O2 plasma etching do not lose their unique electrochemical properties and can be utilized as electrodes for biosensors and electrochemical sensors. Our experimental results also indicate that the ionic conductivity enhancement by O2 plasma can be achieved additionally. [ABSTRACT FROM AUTHOR]

Electricity generation from renewable energy sources is emerging as a result of global carbon emission reduction policies. However, most renewable energy sources are non-dispatchable and cannot be adjusted to meet the fluctuating electricity demands of society. A flexible operation process has been proposed as an effective solution to compensate for the unstable nature of renewable energy sources. Thermal load fluctuations during flexible operation may cause creep–fatigue damage to the high-temperature components of thermal power plants, as they are designed with a focus on creep damage under a constant power level. This study investigated the residual life of high-temperature components, such as a superheater tube and a reheater header, to failure under flexible operation conditions using finite element analysis and empirical models. First, we determined an analytical solution for the straightened superheater tube under thermal conditions and compared it with the numerical solution to verify the numerical models. Through the verified finite element model, the creep–fatigue life of the reheater header was estimated by considering flexible operation factors and employing the Coffin–Manson and Larson–Miller models. Although fatigue damage increases with decreasing minimum load and ramp rate, we confirmed that creep damage significantly affects the residual life during flexible operation. In addition, a surrogate model was proposed to evaluate the residual life of the reheater as a function of the flexible operation factors using the machine learning methodology, based on the results of finite element methods. It can be used to predict its residual life without performing complex thermo-structural analysis and relying on empirical models for fatigue and creep life. We expect our findings to contribute to the efficient operation of thermal power plants by optimizing the flexible operation factors. [ABSTRACT FROM AUTHOR]